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Home & DIY Calculators

Free home improvement calculators for paint, flooring, concrete, mulch, wallpaper, and square footage. Estimate materials and costs before you start any DIY project.

14 free home & diy calculators

Rental Property Investment Calculator

Analyze rental property returns with gross yield, after-tax yield, cap rate, and cash flow. Compare key investment metrics to evaluate real estate deals.

Home Affordability Calculator

Find out how much house you can afford based on your income, debts, and down payment. Get a realistic home buying budget with monthly payment estimates.

Rent vs Buy Calculator

Compare the financial impact of renting versus buying a home over time. See the break-even point and total costs to make an informed housing decision.

Square Footage Calculator

Calculate square footage for rooms, flooring, painting, and landscaping projects. Enter length and width to find the total area in square feet or metres.

How Much Paint Do I Need?

How much paint do I need for a room or one wall? Calculate the gallons of paint you need from your room size, with doors, windows, and extra coats included.

Electricity Cost Calculator

Calculate your electricity cost and energy bill from appliance wattage and kWh usage. Estimate the daily, monthly, and yearly power cost at your electric rate.

Concrete Calculator

Calculate how much concrete you need for any project. Enter your dimensions to find the cubic metres or bags required for slabs, footings, posts, and walls.

Flooring Calculator

Calculate how much flooring material you need and estimate the total cost. Works for hardwood, laminate, tile, and carpet with a waste factor included.

Pool Volume Calculator

Calculate your pool water volume in litres or gallons quickly. Works for rectangular, round, and oval pools, ideal for chemical dosing and water costs.

Wallpaper Calculator

Calculate how many rolls of wallpaper you need for any room. Accounts for pattern repeat, windows, doors, and a waste factor for accurate roll counts.

Mulch Calculator

Calculate how much mulch you need in cubic yards or bags for your garden beds. Enter bed dimensions and depth to get accurate estimates plus total cost.

Lawn Fertiliser Planner

Calculate how much lawn fertiliser to apply based on your lawn size and nitrogen needs. Uses university extension service rates for healthy, even growth.

Leaky Faucet Calculator

Calculate how much water and money a dripping faucet wastes each day, month, and year. Based on USGS data of about 0.25 mL per drip, or 4000 drips a litre.

Rainwater Harvesting Calculator

Calculate how much rainwater you can collect from your roof each year. Enter roof area and local rainfall to estimate annual yield in litres and savings.